diff --git a/td/telegram/Document.cpp b/td/telegram/Document.cpp
index 92e26e92..4aac60f4 100644
--- a/td/telegram/Document.cpp
+++ b/td/telegram/Document.cpp
@@ -6,8 +6,49 @@
 //
 #include "td/telegram/Document.h"
 
+#include "td/telegram/AnimationsManager.h"
+#include "td/telegram/AudiosManager.h"
+#include "td/telegram/DocumentsManager.h"
+#include "td/telegram/StickersManager.h"
+#include "td/telegram/Td.h"
+#include "td/telegram/VideosManager.h"
+#include "td/telegram/VideoNotesManager.h"
+#include "td/telegram/VoiceNotesManager.h"
+
 namespace td {
 
+vector<FileId> Document::get_file_ids(const Td *td) const {
+  vector<FileId> result;
+  if (empty()) {
+    return result;
+  }
+  CHECK(file_id.is_valid());
+
+  result.push_back(file_id);
+  FileId thumbnail_file_id = [&] {
+    switch (type) {
+      case Type::Animation:
+        return td->animations_manager_->get_animation_thumbnail_file_id(file_id);
+      case Type::Audio:
+        return td->audios_manager_->get_audio_thumbnail_file_id(file_id);
+      case Type::General:
+        return td->documents_manager_->get_document_thumbnail_file_id(file_id);
+      case Type::Sticker:
+        return td->stickers_manager_->get_sticker_thumbnail_file_id(file_id);
+      case Type::Video:
+        return td->videos_manager_->get_video_thumbnail_file_id(file_id);
+      case Type::VideoNote:
+        return td->video_notes_manager_->get_video_note_thumbnail_file_id(file_id);
+      default:
+        return FileId();
+    }
+  }();
+  if (thumbnail_file_id.is_valid()) {
+    result.push_back(thumbnail_file_id);
+  }
+  return result;
+}
+
 StringBuilder &operator<<(StringBuilder &string_builder, const Document &document) {
   auto type = [&] {
     switch (document.type) {
diff --git a/td/telegram/Document.h b/td/telegram/Document.h
index 44f0fd56..53393104 100644
--- a/td/telegram/Document.h
+++ b/td/telegram/Document.h
@@ -13,6 +13,8 @@
 
 namespace td {
 
+class Td;
+
 struct Document {
   // append only
   enum class Type : int32 { Unknown, Animation, Audio, General, Sticker, Video, VideoNote, VoiceNote };
@@ -27,6 +29,8 @@ struct Document {
   bool empty() const {
     return type == Type::Unknown;
   }
+
+  vector<FileId> get_file_ids(const Td *td) const;
 };
 
 StringBuilder &operator<<(StringBuilder &string_builder, const Document &document);
diff --git a/td/telegram/Document.hpp b/td/telegram/Document.hpp
index a0a5011f..b703c6bc 100644
--- a/td/telegram/Document.hpp
+++ b/td/telegram/Document.hpp
@@ -9,14 +9,21 @@
 #include "td/telegram/Document.h"
 
 #include "td/telegram/AnimationsManager.h"
+#include "td/telegram/AnimationsManager.hpp"
 #include "td/telegram/AudiosManager.h"
+#include "td/telegram/AudiosManager.hpp"
 #include "td/telegram/DocumentsManager.h"
+#include "td/telegram/DocumentsManager.hpp"
 #include "td/telegram/files/FileId.hpp"
 #include "td/telegram/StickersManager.h"
+#include "td/telegram/StickersManager.hpp"
 #include "td/telegram/Td.h"
 #include "td/telegram/VideosManager.h"
+#include "td/telegram/VideosManager.hpp"
 #include "td/telegram/VideoNotesManager.h"
+#include "td/telegram/VideoNotesManager.hpp"
 #include "td/telegram/VoiceNotesManager.h"
+#include "td/telegram/VoiceNotesManager.hpp"
 
 #include "td/utils/logging.h"
 #include "td/utils/tl_helpers.h"
diff --git a/td/telegram/WebPagesManager.cpp b/td/telegram/WebPagesManager.cpp
index 0725da5b..d9c706fe 100644
--- a/td/telegram/WebPagesManager.cpp
+++ b/td/telegram/WebPagesManager.cpp
@@ -3765,34 +3765,8 @@ vector<FileId> WebPagesManager::get_web_page_file_ids(const WebPage *web_page) c
   }
 
   vector<FileId> result = photo_get_file_ids(web_page->photo);
-  if (web_page->document.file_id.is_valid()) {
-    result.push_back(web_page->document.file_id);
-    FileId thumbnail_file_id;
-    switch (web_page->document.type) {
-      case Document::Type::Animation:
-        thumbnail_file_id = td_->animations_manager_->get_animation_thumbnail_file_id(web_page->document.file_id);
-        break;
-      case Document::Type::Audio:
-        thumbnail_file_id = td_->audios_manager_->get_audio_thumbnail_file_id(web_page->document.file_id);
-        break;
-      case Document::Type::General:
-        thumbnail_file_id = td_->documents_manager_->get_document_thumbnail_file_id(web_page->document.file_id);
-        break;
-      case Document::Type::Sticker:
-        thumbnail_file_id = td_->stickers_manager_->get_sticker_thumbnail_file_id(web_page->document.file_id);
-        break;
-      case Document::Type::Video:
-        thumbnail_file_id = td_->videos_manager_->get_video_thumbnail_file_id(web_page->document.file_id);
-        break;
-      case Document::Type::VideoNote:
-        thumbnail_file_id = td_->video_notes_manager_->get_video_note_thumbnail_file_id(web_page->document.file_id);
-        break;
-      default:
-        break;
-    }
-    if (thumbnail_file_id.is_valid()) {
-      result.push_back(thumbnail_file_id);
-    }
+  if (!web_page->document.empty()) {
+    append(result, web_page->document.get_file_ids(td_));
   }
   if (!web_page->instant_view.is_empty) {
     for (auto &page_block : web_page->instant_view.page_blocks) {